Pharmaceutical composition for preventing or treating neurodegenerative diseases which includes flower extract of daphne genkwa or fractions thereof as active ingredient

ABSTRACT

The present invention relates to a pharmaceutical composition and health functional food for preventing or treating neurodegenerative diseases which include a flower extract of  Daphne genkwa  or fractions thereof as an active ingredient. The pharmaceutical composition and health functional food for preventing or treating neurodegenerative diseases are, not like extracts from stems and/or roots of  Daphne genkwa , free from genotoxicity and have superior prophylactic or treatment effects against neurodegenerative diseases.

BACKGROUND Technical Field

The present invention relates to pharmaceutical composition forpreventing or treating neurodegenerative disease comprising an extractof flower of Daphne genkwa or a fractions thereof as active ingredient.

Background Art

Neurodegenerative diseases are associated with symptoms in which neuronsdegenerate, lose their function, and often die. Patients withneurodegenerative disease may undergo severe deterioration in cognitiveor motor ability. Because these diseases are generally progressive,therefore, the quality of life and life expectancy of the patients maybe considerably reduced.

These diseases include Parkinson's disease (PD), Alzheimer's disease(AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD),fronto-temporal dementia, cortico basal degeneration, progressivesupranuclear palsy (PSP) and other diseases.

Meanwhile, it is known that Nurr1 (nuclear receptor-related 1) proteinis implicated in a considerable number of neurodegenerative diseases.The term “Nurr1” refers to nuclear receptor-related 1 protein, alsoknown as NR4A2 (nuclear receptor subfamily 4, group A, member 2), whichis known to be encoded by the human NR4A2 gene. Although the Nurr1protein is an orphan nuclear receptor whose ligand has not yet beenclearly identified, it was identified that the Nurr1 protein plays a keyrole in maintaining the dopaminergic system in the brain. It is knownthat, when aberrations in the Nurr1 or NR4A2 gene occur, the function ofthe dopaminergic system is damaged to cause Parkinson's disease and awide range of inflammatory and neuropathic diseases, includingrheumatoid arthritis, schizophrenia and manic depression. Parkinson'sdisease is a typical neurodegenerative disease that is caused by Nurr1dysfunction.

Parkinson's disease is one of the major diseases in modern agingsociety, which is characterized by tremor, stiffness, bradykinesia, andgait abnormality, and is a chronic disease caused by a lack ofneurotransmitters called dopamine in the substantia nigra and corpusstriatum of the brain.

Known drugs for treating Parkinson's disease include L-dopa drugs,dopamine receptor agonists, anti-cholinergic drugs, Eldepryl, etc. Mostof these drugs do not provide causal treatment of Parkinson's disease,but act to control conditions, and thus need to be administeredcontinually. Although many medicines have been produced andcommercialized for the treatment of Parkinson's disease so far, anessential therapeutic agent for completely treating Parkinson's diseasehas not yet been developed.

Recently, it has been reported that compounds that activate the functionof Nurr1, which plays an important role in the differentiation, growthand maintenance of dopaminergic neurons, have medicinal effects onParkinson's disease and can be applied as a disease target of atherapeutic agent for Parkinson's disease.

In the Korean Patent Registration No. 10-1631589 filed by the presentapplicant, it has been confirmed that the extract of stalk and/or rootof Daphne genkwa is involved in the activation of Nurr1 and the symptomsof Parkinson's disease are alleviated when administered to an animalmodel of Parkinson's disease.

However, it has been confirmed that the extract of stalk and/or root ofDaphne genkwa proposed by the present applicant were genotoxic in thebacterial reverse mutation assay and the chromosome aberration assayduring the non-clinical stability testing for the development of naturalproduct new drug.

In order to solve such problems, the inventors of the present inventionhave found that flower of Daphne genkwa which is a well-knowntraditional oriental medicine is more effective for prevention ortreatment of neurodegenerative diseases without genetic toxicity, thuscompleting the present invention.

PRIOR ART Patent

-   Korean Patent Registration No. 10-1631589

DETAILED DESCRIPTION OF THE INVENTION Technical Problem

The object of present invention is to provide pharmaceutical compositionfor preventing or treating neurodegenerative disease comprising theextract of flower of Daphne genkwa or a fractions thereof as activeingredient.

Also, the present invention is to provide a health functional food forpreventing or ameliorating neurodegenerative disease comprising theextract of flower of Daphne genkwa or a fractions thereof.

Technical Solution

Hereinafter, the present invention will be described in detail.

In one aspect of the present invention, the present invention provides apharmaceutical composition for preventing or treating neurodegenerativediseases comprising an extract of flower of Daphne genkwa or a fractionthereof as an active ingredient.

As used herein, the term “Daphne genkwa” refers to a deciduous shrub ofdicotyledonous Myrtales thymelaeaceae, and is also called lilac daphne.

It grows mainly on the seashore. In Chinese medicine, it is used totreat symptoms such as diuresis, hydrops and nephritis. Dried-buds ofDaphne genkwa are called “flower” or “uan flower” and are used asmedicinal materials and are known to have some toxicity. It is knownthat the extract of flower of Daphne genkwa contains genkwanin,hydroxygenkwanin, apigenin and sitosterol, as well as benzoic acid andirritating essential oil substance.

As used herein, the term “extract of flower of Daphne genkwa” refers toan extract obtained from the flower or bud of Daphne genkwa, preferablyan extract obtained by extracting the flower or bud of Daphne genkwawith water or organic solvent, and specifically an extract obtained byextracting the flower or bud of Daphne genkwa with water, C₁-C₄ loweralkyl alcohol or a mixed solvent thereof.

The extract of flower of Daphne genkwa according to an embodiment of thepresent invention is preferably an extract obtained by extracting with80% ethanol.

According to one embodiment of the present invention, the extract offlower of Daphne genkwa is obtained using water, an organic solvent suchas C₁-C₄ lower alkyl alcohol such as methanol, ethanol, butanol or thelike, or an C₁-C₄ lower alkyl alcohol aqueous solution to the flower orbud of Daphne genkwa. The extract of flower of Daphne genkwa may includeGenkwanin N or Yuanhuacin compounds.

The Genkwanin N can be produced by a method known to those skilled inthe art as a terpenoid represented by Formula 1, specifically, aditerpene ester compound, and preferably can be extracted and separatedfrom the flower or bud of Daphne genkwa.

The Yuanhuacin can be produced by a method known to those skilled in theart as a terpenoid represented by Formula 2, specifically, a diterpeneester compound, and preferably can be extracted and separated from theflower or bud of Daphne genkwa.

The term “fraction” used in the present invention means an activefraction obtained by fractionating a substance having an activity ofinterest in the present invention from the extract of flower of Daphnegenkwa a using a specific solvent.

In another example of the present invention, the extract of flower ofDaphne genkwa is obtained by separating a fraction layer of each solventusing a mixed solvent of an organic solvent such as hexane, ethylacetate, butanol, or distilled water, and the like, and the activeingredient can be isolated and purified in high purity using aseparation method known in the art such as chromatography to producefractions. Fractions obtained through various purification methods arealso included in the fractions of the present invention. The fractionsof the extract of flower of Daphne genkwa may include Genkwanin N orYuanhuacin compounds.

The extract of flower of Daphne genkwa or the fractions thereof of thepresent invention may include not only the extract obtained by theabove-mentioned extraction solvent but also the extract obtained throughordinary purification process. The inventors of the present inventionconfirmed that genotoxicity was observed in a bacterial reverse mutationassay and a chromosome aberration assay in the non-clinical stabilitytrial for development of natural products as new drugs, in the case ofthe extract derived from the stem and root of Daphne genkwa of KoreanParent Registration No. 10-1631589 filed by the present applicant (FIG.1A.). Otherwise, genetic toxicity of the extract of flower of Daphnegenkwa was examined, and it was confirmed that neither the bacterialreverse mutation assay nor the chromosome aberration assay showedgenotoxicity (FIG. 1B).

The present inventors also compared and analyzed the active ingredientsof the extract of flower of Daphne genkwa and of the extract derivedfrom the stem and root of Daphne genkwa, and found that both Genkwanin Nand Yuanhuacin were detected as active ingredients in both the extractof flower of Daphne genkwa and the extract derived from the stem androot of Daphne genkwa. As a result of quantifying each activeingredient, it was confirmed that the amounts of Genkwanin N andYuanhuacin of the extract of flower of Daphne genkwa were about 7.32times and 1.23 times greater than those derived from the stem and rootof Daphne genkwa, respectively (FIG. 2).

Moreover, as a result of comparing the activity of the Nurr1 from theextract of flower of Daphne genkwa and the extract derived from the stemand root of Daphne genkwa, it was confirmed that the extract of flowerof Daphne genkwa of the present invention showed higher activity thanthe extract derived from the stem and root of Daphne genkwa (FIG. 4).

Furthermore, the present inventors have also carried out theapomorphine-induced rotation test after feeding a mixture containing theextract of flower of Daphne genkwa to a 6-OHDA-induced animal model ofParkinson's disease. As a result, it was confirmed that the number ofrotation was significantly reduced when compared with We vehicle-treatedgroup (control group) (FIG. 5).

Thus, the present inventors have found that the extract of flower ofDaphne genkwa increases the activity of Nurr1 and is effective forpreventing or treating various diseases caused by the damage ofdopaminergic neurons directly affected by the activity of Nurr1 forexample, various neurodegenerative diseases caused by, dysfunction ofNurr1 other than Parkinson's disease and Parkinson's disease.

Therefore, the pharmaceutical composition comprising the extract offlower of Daphne genkwa of the present invention or fractions thereof asan active ingredient has an effect on the activation of the Nurr1 sothat it is effective for preventing or treating various diseases causedby the damage of dopaminergic neurons directly affected by the activityof Nurr1, for example, various neurodegenerative diseases caused bydysfunction of Nurr1 other than Parkinson's disease and Parkinson'sdisease.

As used herein, the term “neurodegenerative diseases” refers to diseasesassociated with conditions in which neurons degenerate, lose theirfunction, and often die. The neurodegenerative diseases include, but arenot limited to, Parkinson's disease (PD), Alzheimer's disease (AD),amyotrophic lateral sclerosis (ALS), Huntington's disease (HD),frontotemporal dementia, cortico basal degeneration, and progressivesupranuclear palsy (PSP). Preferably, the neurodegenerative diseaseaccording to the present invention is Parkinson's disease.

The pharmaceutical composition of the present invention may include apharmaceutically acceptable carrier excipient or diluent in addition tothe active ingredient or its fractions described above. Examples of thecarrier, excipient and diluent include lactose, dextrose, sucrose,sorbitol, mannitol, erythritol, maltitol, starch, acacia rubber,alginate, gelatin, calcium phosphate, calcium silicate, cellulose,methylcellulose, microcrystalline cellulose, Polyvinylpyrrolidone,water, methylhydroxybenzoate, propylhydroxybenzoate talc, magnesiumstearate and mineral oil.

The pharmaceutical composition of the present invention may beformulated in the oral dosage form of powders, granules, tablets,capsules, suspensions, emulsions syrups, aerosols, etc. or in the formof an external preparation, a suppository or a sterile injectionsolution according to conventional methods. In detail, when formulating,it can be prepared by using diluents or excipients such as fillers,weighing agents, binders, humectants, disintegrants, surfactants and thelike which are generally used. Solid formulations for oraladministration include, but are not limited to, tablets, pills, powders,granules, capsules, and the like. Such a solid preparation may beprepared by mixing at least one excipient such as starch, calciumcarbonate, sucrose, lactose, gelatin and the like. In addition to simpleexcipients, lubricants such as magnesium stearate and talc may also beused. Liquid formulations for oral administration, liquid paraffin, andvarious excipients such as wetting agents, sweeteners, fragrances,preservatives and the like may be also used. Formulations for parenteraladministration include sterile aqueous solutions, non-aqueous solvents,suspensions, emulsions, lyophilized preparations and suppositories.Non-aqueous solvents and suspensions may include propylene glycol,polyethylene glycol, vegetable oils such as olive oil, injectable esterssuch as ethyl oleate, and the like. Examples of suppositories includewithexol, macrogol, tween 61, cacao butter, laurin, and glycerogelatin.

The pharmaceutical composition of the present invention can beadministered orally or parenterally (for example, intravenously,subcutaneously, intraperitoneally or topically) according to theintended method.

The pharmaceutical composition according to the present invention may beadministered in a pharmaceutically effective amount, that is, in anamount sufficient to prevent or treat the disease at a reasonablebenefit/risk ratio applicable to medical prevention or treatment. Theeffective dosage level of the composition may be determined depending onthe severity of the disease, the activity of the drug, the patient'sage, weight, physical condition and sex, the patient's sensitivity tothe drug, the time of administration of the inventive composition used,the route of administration of the composition, the excretion rate, theduration of treatment, factors including drugs used in combination withor contemporaneously with the composition of the present inventionemployed, and other factors well known in the medical arts, but may besuitably selected by those skilled in the art.

The dose or the dosage of the pharmaceutical composition comprising theextract of flower of Daphne genkwa or the fraction thereof according tothe present invention as an active ingredient may vary depending on thepatient's age, physical condition, body weight etc., but, in general, itis preferable to administer it within the range of 0.01 to 1,000 mg/kg(weight)/day. And, it can be applied once a day or several times a daywithin a range of effective doses per day.

As another embodiment for achieving the above object the presentinvention provides a health functional food for preventing orameliorating a neurodegenerative disease comprising an extract of flowerof Daphne genkwa or a fraction thereof.

The term “health functional food” used in the present invention means afood prepared and processed using raw materials or ingredients havinguseful functions in the human body in accordance with Law No. 6727 onHealth Functional Foods, and “functional” means that the structure andfunction of the human body is ingested for the purpose of obtainingnutritional control or physiological effects and other useful effectsfor health use.

When the extract of flower of Daphne genkwa or a fraction thereof of thepresent invention is used as a food additive, the above extract or thefraction thereof may be added to the food or beverage as it is or incombination with other food additives. When the extract of flower ofDaphne genkwa or the fraction thereof of the present invention is addedduring the production of food or beverage the addition amount thereof isnot particularly limited, but may be added in an amount of 1˜5% byweight, preferably 1˜3% by weight, based on the weight of the finalfood. However, in the case of long-term intake for the purpose of healthand hygiene or for the purpose of controlling health, the additionamount may be less than the above range, but in the case where there isno problem in terms of safety, it may be used in an amount exceeding theabove range.

The type of the food or beverage is not particularly limited, butincludes all foods or beverages in a conventional sense, preferablymeat, sausage, bread, chocolate candy, snack, confectionery pizza,ramen, noodles, gums, dairy products including ice cream, various soups,beverages, tea, drinks, alcoholic beverages and vitamin complexes.

When the extract of flower of Daphne genkwa or a fraction thereof of thepresent invention is added to a food, it is preferable to add togetherwith an auxiliary component such as various nutrients, vitamins,electrolytes, flavors, colorants, pectic acid and its salts, alginicacid and its salts, organic acids, protective colloid thickeners, pHadjusting agents, stabilizers, preservatives, glycerin, alcohols and thelike.

When the extract of flower of Daphne genkwa or the fraction thereof ofthe present invention is added to beverages, various sweeteners ornatural carbohydrates may be added as an additional ingredient such asordinary beverages. At this time, the sweetener is not particularlylimited, but may be a natural sweetener such as tau marin or steviaextract or a synthetic sweetener such as saccharin or aspartame.Examples of the natural carbohydrate include, but are not limited to,monosaccharides (for example, glucose and fructose), disaccharides (forexample, maltose and sucrose), polysaccharides (for example, dextrin andcyclodextrin), or sugar alcohols (for example, xylitol, sorbitol,erythritol, etc.) may be used.

The safety of the extract of flower of Daphne genkwa or its fractions ofthe present invention has been confirmed, and a health functional foodcomprising the same can prevent or ameliorate the symptoms ofneurodegenerative diseases.

In another aspect of the present invention, the present inventionprovides a method for preventing or treating a neurodegenerativedisease, comprising the step of administering a pharmaceuticalcomposition comprising the extract of flower of Daphne genkwa or afraction thereof as an active ingredient to a subject in need thereof.

The terms used in the present invention are the same as those describedabove, such as ‘Daphne genkwa’, ‘the extract of flower of Daphnegenkwa’, ‘fraction’, ‘neurodegenerative diseases’, and ‘administration’.

In the present invention, the subject refers to an animal, and istypically a mammal capable of exhibiting beneficial effects in thetreatment with the extract of the present invention. Preferred examplesof such a subject include primates such as humans. Such subjects alsoinclude subjects with neurodegenerative disease symptoms or at risk ofhaving such symptoms.

As another embodiment for achieving the above object, the presentinvention provides the use of the extract of flower of Daphne genkwa ora fraction thereof for preventing or treating of neurodegenerativediseases.

As another embodiment for achieving the above object, the presentinvention provides the use of the extract of flower of Daphne genkwa ora fraction thereof for producing a medicament having an effect ofpreventing or treating a neurodegenerative disease.

The terms used in the present invention are the same as those describedabove, such as ‘Daphne genkwa’, ‘the extract of flower of Daphnegenkwa’, ‘fraction’, ‘neurodegenerative diseases’.

Effects of the Invention

The pharmaceutical composition comprising the extract of flower ofDaphne genkwa or a fraction thereof of the present invention as anactive ingredient exhibits an excellent effect of restoring theinhibition of the activity of Nurr1 by nerve injury without showing anyside effects, and has an excellent effect in the prevention or treatmentof neurodegenerative diseases caused by inhibition of the activity ofNurr1.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows the induction of a reverse mutation of the extract ofstalk and/or root of Daphne genkwa,

FIG. 1B shows that the extract of flower of Daphne genkwa was notmutagenic.

TA98 refers to the Salmonella typhimurium strain TA98, and TA1535 refersto the Salmonella typhimurium strain TA1535, and TA1537 refers to theSalmonella typhimurium strain TA1537.

FIG. 2 shows the results of analysis of the active ingredient of theextract of flower of Daphne genkwa by LC-MS/MS method.

A) is the standard material DGH-1 (m/z 105.2>591.2) and DGH-2 (m/z105.1>659.2), in B), DGF-EX is the extract of flower of Daphne genkwa,DG-EX is the extract of stalk and/or root of Daphne genkwa.

FIG. 3 is a graph showing the change in Nurr1 activity according to theconcentration of extract of flower of Daphne genkwa through luciferaseassay.

Con-3 ul means control group (1% DMSO). (**: p<0.01).

FIG. 4 is a graph showing the results of comparative experiments showingthe change of Nurr1 activity according to each concentration of extractof stalk and/or root of Daphne genkwa and of extract of flower of Daphnegenkwa through luciferase assay. DG-EX refers to the extract of stalkand/or root of Daphne genkwa, and DGF-EX refers to the extract of flowerof Daphne genkwa.

FIG. 5 is a graph showing the results of a rotation test after two or 4weeks of feeding of the extract of flower of Daphne genkwa from 6-OHDA(6-hydroxydopamine) induced animal model of Parkinson's disease.

FIG. 6 shows immunohistochemical analysis of changes in dopaminergicneurons in the substantia nigra of midbrain after 4 weeks of feeding ofthe extract of flower of Daphne genkwa from 6-OHDA (6-hydroxydopamine)induced animal model of Parkinson's disease.

FIG. 7 is a graph comparing the number of dopaminergic neurons in thesubstantia nigra of midbrain after 4 weeks of feeding of the extract offlower of Daphne genkwa in 6-OHDA (6-hydroxydopamine) induced animalmodel of Parkinson's disease. PBS means a group not Injected with6-OHDA, 6-OHDA means a group injected in 6-OHDA, 6OD+10 means a groupfed with 10 mg/kg of the extract of flower of Daphne genkwa after 6-OHDAinjection, 6OD+50 means a group fed with 50 mg/kg of the extract offlower of Daphne genkwa after 6-OHDA injection.

DETAILED DESCRIPTION

Hereinafter, the present invention will be described in more detail withreference to examples. However, these examples are for illustrativepurposes only, and the scope of the present invention is not limited tothese examples.

Comparative Example 1: Genotoxicity Test of the Extract of Stalk and/orRoot of Daphne genkwa

In order to confirm in vitro genotoxicity of the extract of stalk and/orroot of Daphne genkwa according to Korean Patent Registration No.10-1631589 filed by the present applicant, a bacterial reverse mutationassay and a chromosomal aberration test were performed as describedbelow.

1-1. Production of the Extract of Stalk and/or Root of Daphne genkwa

14 kg of stem of Daphne genkwa and 6 kg of root of Daphne genkwa werefinely cut and immersed in 120 L of 80% ethanol for 48 hours, andfiltered to separate it into a solid component and a first liquidcomponent. The separated solid component were again immersed in 120 L80% ethanol for 24 hours and filtered to obtain a second liquidcomponent. The obtained first liquid component and the second liquidcomponent were mixed with each other, and the mixture was concentratedunder reduced pressure. The residue was freeze-dried, thereby obtaining1140.9 g of the extract of stalk and/or root of Daphne genkwa(hereinafter referred to as “DG-EX”)

1-2 Bacterial Reverse Mutation Assay

In order to confirm genotoxicity of the extract of stalk and/or root ofDaphne genkwa, a bacterial reverse mutation assay was conducted on thebasis of the guidelines of Ministry of Food and Drug Safety byBiotoxtech, a GLP (Good Laboratory Practice) organization.

In order to confirm the genomic mutation induction of DG-EX obtained inthe Test 1-1, a bacterial reverse mutation assay for the presence ofmetabolic activation system (S9+) and non-existence (S9−) was performedwith Salmonella typhimurium TA98, TA100, TA1535, TA1537, histidinerequiring strain, and Escherichia coli WP2uvrA (pKM101), a tryptophanrequiring strain.

(1) Capacity Setting Test

In order to set the maximum dose of the bacterial reverse mutation assayof present test, the recommended dose of 5,000 μg/plate was used as themaximum capacity, and the capacity setting test was carried out at1,250, 313, 78.1, and 19.5 μg/plate in common rate 4.

As a result, it was found that inhibition of growth by DG-EX wasobserved on 5,000 μg/plate of TA98 strain, and above 313 μg/plate ofTA100, TA1535 and TA1537 strains in the absence of the metabolismactivation system, and on 5,000 μg/plate of TA100, TA1535 and TA1537strains in the presence of metabolic activation system. Growthinhibition was not observed in TA98 and WP2uvrA (pKM101) strains in thepresence of metabolic activation system, and in WP2uvrA (pKM101) strainin the absence of metabolic activation system.

Therefore, the capacity of the bacterial reverse mutation assay as thepresent test was set as shown in Table 1 below. In addition, a negativecontrol and a positive control were set.

TABLE 1 strain S9 mix DOS (μg/plate) TA98 − 5,000, 2,500, 1,250, 625,313, 156 − 5,000, 2,500, 1,250, 625, 313 TA100, TA1535, TA1537 − 313,156, 78.1, 39.1, 19.5, 9.77 − 5,000, 2,500, 1,250, 625, 313, 156WP2uvrA(pKM101) −/+ 5,000, 2,500, 1,250, 625, 313

Precipitation of the test substance DG-EX was not observed at all dosesin the presence and absence of metabolic activation system.

(2) Bacterial Reverse Mutation Assay

Each strain was treated with the test substance DG-EX at the aboveconcentrations and cultured, and the number of bacterial reversemutation colonies was visually counted. The results are shown in Table 2below.

TABLE 2 Individual Dose level revertant Strain Test substance (μg/plate)colony counts Mean S.D. TA98 Dimethyl sulfoxide 0 27, 26, 24 26 2 DG-EX313 28, 25, 30 28 3 625 30, 31, 35 32 3 1,250 36, 43, 42 40 4 2,500 52,45, 43 47 5 5,000 36, 30, 36 34 3 2-Aminoanthracene (2-AA) 1.0 358, 366,362 362 4 TA100 Dimethyl sulfoxide 0 118, 117, 115 117 2 DG-EX 156 110,117, 103 110 7 313 116, 116, 123 118 4 625 123, 127, 133 128 5 1,250192, 181, 205 193 12 2,500 171, 176, 184 177 7 5,000 117*, 110*, 119*115 5 2-Aminoanthracene (2-AA) 2.0 596, 608, 572 592 18 TA1535 Dimethylsulfoxide 0 9, 11, 7 9 2 DG-EX 156 7, 10, 9 9 2 313 6, 8, 8 7 1 625 9,9, 5 8 2 1,250 10, 8, 10 9 1 2,500 12, 15, 13 13 2 5,000 15*, 15*, 11*14 2 2-Aminoanthracene (2-AA) 3.0 98, 112, 94 101 9 TA1537 Dimethylsulfoxide 0 14, 13, 16 14 2 DG-EX 156 20, 18, 17 18 2 313 20, 18, 21 202 625 16, 17, 19 17 2 1,250 32, 30, 37 33 4 2,500 25*, 27*, 29* 27 25,000 14*, 16*, 17* 16 2 2-Aminoanthracene (2-AA) 3.0 128, 136, 122 1297 WP2uvrA(pKM101) Dimethyl sulfoxide 0 163, 150, 151 155 7 DG-EX 313170, 152, 169 164 10 625 170, 176, 166 171 5 1,250 180, 163, 162 168 102,500 176, 159, 169 168 9 5,000 168, 167, 153 163 8 2-Aminoanthracene(2-AA) 2.0 445, 462, 480 462 18 S.D: Standard Deviation *indicatesgrowth inhibition

As a result, at the 1,250 μg/plate of the TA1537 strain in the presenceof the metabolic activation system, the number of reverse mutationcolonies increased more than twice as much as that of the negativecontrol, and above 2,500 μg/plate, growth inhibition by DG-EX wasobserved and the number of reverse mutation colonies tended to decrease.

In TA98, TA100, TA1535, TA1537 and WP2uvrA (pKM101) strains in theabsence of metabolic activation system and TA98, TA100, TA1535 andWP2uvrA (pKM101) strains in the presence or metabolic activation system,regardless of the presence or absence of the metabolic activation systemin the test substance group, the number of reverse mutation colonies didnot exceed twice the negative control group and no dose-dependentincreases were observed for all the strains of each strain.

The number of reverse mutation colonies of the positive control for eachstrain was more than twice as high as that of the negative control. Theresults are shown in FIG. 1.

As shown in FIG. 1A, under the present test conditions, the testsubstance DG-EX was found to be mutagenic by increasing the number ofreverse mutation colonies in the TA1537 strain in the presence of themetabolic activation system more than twice that of the negativecontrol.

1-3 Chromosome Aberration Assay

In order to confirm genotoxicity of extract of stalks and root of Daphnegenkwa, a chromosome aberration assay was performed on the basis of theguidelines of Ministry of Food and Drug Safety in Biotoxtech, a GLP(Good Laboratory Practice) organization.

To confirm the structural aberration of the chromosome of DG-EX obtainedin the Test substance 1-1, the presence of structural aberration of thechromosome was evaluated using CHL (Chinese Hamster Lung)/IU cells, amammalian cell line.

(1) Cell Proliferation Inhibition Test

For the highest capacity setting of this test, the chromosome aberrationassay, cell proliferation inhibition test was carried out with thehighest dose of DG-EX 5,000 μg/ml at the following doses of 2,500,1,250, 625, 313, 156, 78.1, 39.1, and 19.5 μg/ml. The relativepopulation doubling (RPD) after DG-EX treatment was calculated and usedas an indicator of cell proliferation inhibition.

As a result, cytotoxicity was observed in the presence or absence of themetabolic activation system and in the absence of the metabolicactivation system of the continuous treatment method. The dose thatspecifically inhibited cell proliferation by more than 50% was more than1,250 μg/mL in the presence and absence of the metabolic activationsystem of the short-term treatment method and more than 625 μg/mL in theabsence of the metabolic activation system or the continuous treatmentmethod.

Therefore, the capacity of this test was set as shown in Table 3 below.Also, a negative control and a positive control were set.

TABLE 3 treatment S9 mix dose of the present test (μg/mL) short-termtreatment − 1,200, 600, 300, 150 + 900, 450, 225, 113 continuoustreatment − 600, 300, 150, 75.0

The precipitation of the test substance was observed at more than 2,500μg/mL in the presence and absence of the metabolic activation system ofthe short-term treatment method and in the absence of the metabolicactivation system of the continuous treatment method.

(2) Chromosome Aberration Assay

As a result of the chromosome aberration assay, the frequencies of cellswith numerical aberration were significantly increased at 12.5% and13.0% at 450 μg/mL and 900 μg/mL in the presence of the metabolicactivation system of the short-term treatment method, which wasstatistically significantly increased when compared with the negativecontrol (0%). The frequencies of cells with structural aberration were6.0 and 8.0%, respectively, and statistically significant increase whencompared with negative control (0%) (data not shown).

In the absence of the metabolism activity system of the short-termtreatment method and in the absence of the metabolism activity system ofthe continuous treatment method, the frequency of chromosome aberrationwas less than 5%, and no chromosomal aberration was observed, and nostatistical significance was observed when compared with the negativecontrol group.

In the positive control group for each treatment group, the frequency ofcells with aberrations was more than 10%, which was statistically higherthan that in the negative control group.

Thus, in order to clarify the positive results of the structuralaberration in the presence of the metabolic activation system of theshort-term treatment method, confirmation tests were carried out in thesame manner as in this test with the capacity of the following Table 4.

TABLE 4 treatment S9 mix dose of confirmation test (μg/mL) short-termtreatment + 1,200, 1,100, 1,000, 900

As a result of the confirmation test the frequency of cells withnumerical aberration was confirmed to be 12.5, 11.5, 10.0 and 8.5% at900, 1,000, 1,100 and 1,200 μg/ml in the presence of the metabolicactivation system of the short-term treatment method, and wasstatistically significantly increased when compared with the negativecontrol group. The frequencies of cells with structural aberrations werefound to be 7.5, 7.0, 8.5 and 4.5%, which was statisticallysignificantly increased when compared to the negative control group. Theresults are shown in Table 5 below.

TABLE 5 Trt-Rec No. of Number of cells with structural aberrationsNumber of cells with Test Dose RPD S9 Time cell gap total (%) numericalaberrations substance (μg/mL) (%) mix (hr) analyzed ctb csb cte cse frgctg csg gap− gap+ end pol total (%) Others^(a)) Dimethyl 0 100 + 6-18100 1 0 0 0 0 0 0 1 1 0 0 0 0 sulfoxide 100 0 0 0 0 0 0 0 (0.5) (0.5) 00 (0.0) DG-EX 900 66.5 + 6-18 100 1 0 6 0 0 0 0 15## 15 0 12 25## 0 1002 0 5 1 0 0 0 (7.5) (7.5) 0 13 (12.5) 0 1,000 72.6 + 6-18 100 0 0 7 0 00 0 14## 15 0 12 23## 0 100 1 0 5 1 0 1 0 (7.0) (7.5) 0 11 (11.5) 1,10060.0 + 6-18 100 2 0 7 0 0 2 0 17## 18 0 10 20## 0 100 3 0 6 0 0 0 0(8.5) (9.0) 0 10 (10.0) 1,200 53.2 + 6-18 100 2 0 2 1 0 0 0 9## 9 0 917## 0 100 0 0 4 0 0 0 0 (4.5) (4.5) 0 8 (8.5) B[a]P 20 41.3 + 6-18 1003 0 15 0 0 0 0 40* 40 0 1 2 0 100 3 0 19 0 0 0 0 (20.0) (20.0) 0 1 (1.0)Abbreviation: ctg: chromatid gap, csg: chromosome gap, ctb: chromatidbreak, cte: chromatid exchange, csb: chromosome break, cse: chromosomeexchange, frg: fragmentation, end: endoreduplication, pol: polyploidy,B[a]P: Benzo[a]pyrene, RPD: Relative Population Doubling, Trt-Rec time:Treatment-Recovery times, gap−: total number of cells with structuralaberration except gap, gap+: total number of cells with structuralaberration including gap ^(a))Excluded from the number of cells withchromosomal aberrations. *p < 0.01, #p < 0.05, ##p < 0.01:

Based on the above results, under the test conditions, the testsubstance DG-EX showed a frequency of cells having numerical aberrationof 10% or more and a frequency of cells having a structural aberrationof 5% or more and 10% or less in the presence of the metabolicactivation system of the short-term treatment method, and was confirmedto have a chromosome aberration.

Example 1: Preparation of Extract of Flower of Daphne genkwa

3.5 kg of flower of Daphne genkwa was immersed in 70 L of 80% ethanolfor 48 hours and filtered to separate a solid component and a firstliquid component. The separated solid component were again immersed in70 L of 80% ethanol for 24 hours and filtered to give a second liquidcomponent. The obtained first liquid component and the second liquidcomponent were mixed, the mixture was concentrated under reducedpressure. The residue was freeze-dried, thereby obtaining 859 g ofextract of flower of Daphne genkwa (hereinafter referred to as“DGF-EX”).

Example 2: Analysis of Active Ingredients of Extract of Flower of Daphnegenkwa

The active ingredient of DGF-EX, an extract of flower of Daphne genkwaobtained in Example 1, was analyzed. For comparison, the activeingredient of DG-EX, the extract derived from the stem and root ofDaphne genkwa obtained in Comparative Example 1-1, was also analyzed.

There are two active ingredients of DGH-1 and DGH-2 in the extractderived from the stem and root of Daphne genkwa. DGH-1 has very low UVextinction coefficient and it is very difficult to analyze DGH-1 in theextract by HPLC UV method.

Therefore, in order to effectively analyze both the active substancesDGH-1 and DGH-2 in the extracts, they were analyzed by the multiplereaction monitoring (MRM) with LC-MS/MS. The MRM is a method ofanalyzing a specific substance in a complex sample by detecting a parention having a specific product ion.

As a result, the standards DGH-1 and DGH-2 were detected at 3.81 min and6.99 min, respectively, and detected at 1.05×10⁴ and 1.8×10⁴ intensityat 0.1 μg injection, respectively, with similar sensitivities to the MRMmethod (FIG. 2).

Each extract was dissolved in MeOH at a concentration of 10 μg/mL andanalyzed by MRM method with LC-MS/MS after 10 μl by HPLC. The activeingredients DGH-1 and DGH-2 were detected in both the extract of flowerof Daphne genkwa (DGF-EX) and the extract derived from the stem and rootof Daphne genkwa (DG-EX) (FIG. 2B).

Example 3: Chromosome Aberration Assay of the Extract of Flower ofDaphne genkwa

In order to confirm in vitro genotoxicity of the extract of flower ofDaphne genkwa obtained in Example 1, a bacterial reverse mutation assayand a chromosome aberration assay were performed as described below.

3-1 Bacterial Reverse Mutation Assay

In order to confirm genotoxicity of the extract of flower of Daphnegenkwa, a bacterial reverse mutation assay was conducted on the basis ofthe guideline of Ministry of Food and Drug Safety in Biotoxtech, a GLP(Good Laboratory Practice) organization.

In order to confirm the genomic mutation induction of DGF-EX obtained inthe Test 1, a bacterial reverse mutation assay in the presence ofmetabolic activation system (S9+) and non-existence (S9−) was performedwith Salmonella typhimurium TA98, TA100, TA1535, TA1537, histidinerequiring strain and Escherichia coli WP2uvrA (pkM101), atryptophan-requiring strain.

(1) Capacity Setting Test

In order to set the maximum dose of the bacterial reverse mutation assayof present test, the recommended dose of 5,000 μg/plate was used as themaximum capacity, and the capacity setting test was carried out at1,250, 313, 78.1, and 19.5 μg/plate in common rate 4.

As a result, it was found that inhibition of growth by DGF-EX wasobserved above 1,250 μg/plate of TA98 and TA1535 strain, above 313μg/plate of TA100 strain, above 78.1 μg/plate of TA1537 strain in theabsence of the metabolism activation system and on 5,000 μg/plate ofTA98 and TA 1535 strains, and above 1,250 μg/plate of TA100 and TA1537strains in the presence of the metabolic activation system. Growthinhibition was not observed in strain WP2uvrA (pKM101) in the presenceand absence of the metabolic activation system.

Therefore, the capacity of the bacterial reverse mutation assay as thepresent test was set as shown in Table 6 below. In addition, a negativecontrol and a positive control were set.

TABLE 6 STRAINS S9 mix dose of the present test (μg/plate) TA98, TA1533− 1,200, 625, 313, 156, 78.1, 39.1 + 5,000, 2,500, 1,250, 625, 313, 156TA100 − 313, 156, 78.1, 39.1, 19.5, 9.77 + 1,250, 625, 313, 156, 78.1,39.1 TA1537 − 78.1, 39.1, 19.5, 9.77, 4.88, 2.44 + 1,250, 625, 313, 156,78.1, 39.1 WP2uvrA(pKM101) −/+ 5,000, 2,500, 1,250, 625, 313(2) Bacterial Reverse Mutation Assay

Each strain was treated with the test substance DGF-EX at the aboveconcentrations and cultured, and the number of reverse mutation colonieswas visually counted. The results are shown in Table 7 below.

TABLE 7 Dose level Individual revertant Strain Test substance (μg/plate)colony counts Mean S.D. TA98 Dimethylsulfoxide 0 24, 24, 27 25 2 DGF-EX156 25, 27, 25 26 1 313 35, 24, 27 29 6 625 35, 30, 29 31 3 1,250 29,22, 26 26 4 2,500 35*, 22*, 27* 28 7 5,000 22*, 25*, 22* 23 22-Aminoanthracene (2-AA) 1.0 436, 432, 452 440 11 TA100Dimethylsulfoxide 0 75, 87, 85 82 6 DGF-EX 39.1 80, 87, 91 86 6 78.1 73,87, 92 84 10 156 72, 83, 95 83 12 313 91, 87, 79 86 6 625 81, 84, 83 832 1,250 73*, 67*, 81* 74 7 2-Aminoanthracene (2-AA) 2.0 811, 853, 849838 23 TA1535 Dimethylsulfoxide 0 9, 8, 10 9 1 DGF-EX 156 9, 9, 9 9 0313 10, 8, 11 10 2 625 11, 11, 10 11 1 1,250 10, 8, 7 8 2 2,500 8*, 8*,6* 7 1 5,000 4*, 7*, 5* 5 2 2-Aminoanthracene (2-AA) 3.0 172, 170, 151164 12 TA1537 Dimethylsulfoxide 0 16, 11, 14 14 3 DGF-EX 39.1 15, 14, 1916 3 78.1 14, 18, 14 15 2 156 18, 19, 15 17 2 313 20, 23, 19 21 2 62510*, 13*, 12* 12 2 1,250 11*, 8*, 4* 8 4 2-Aminoanthracene (2-AA) 3.0235, 210, 214 220 13 WP2uvrA(pKM101) Dimethylsulfoxide 0 161, 168, 177169 8 DGF-EX 313 166, 172, 164 167 4 625 165, 149, 154 156 8 1,250 151,160, 176 162 13 2,500 150, 163, 178 164 14 5,000 179, 153, 162 165 132-Aminoanthracene (2-AA) 2.0 549, 543, 543 545 3 S.D: Standard Deviation*indicates growth inhibition

As a result the number of reverse mutation colonies did not exceed twicethe negative control group, and no dose-dependent increase was observedfor all capacities of each strain, regardless of the presence or absenceof metabolic activation system in the test substance group. The numberof positive mutant colonies for each strain was more than twice as highas that of the negative control. The results are shown in FIG. 1.

As shown in FIG. 1B, the test substance DGF-EX showed the number ofreverse mutation colonies not more than 2 times that of the negativecontrol for all doses in the stain TA98, TA1535, and TA1537 in thepresence of the metabolic activity system, and showed no mutagenicity.

The inhibition of growth by test material was observed above 625μg/plate of TA98 and TA1535 strain, above 156 μg/plate of TA100 strain,on 87.1 μg/plate of TA1537 strain in the absence of the metabolismactivation system, and above 2,500 μg/plate of TA98 and TA1535 strains,and on 1,250 μg/plate of TA100 and above 625 μg/plate TA1537 strains inthe presence of the metabolic activation system. Growth inhibition wasnot observed in strain WP2uvrA (pKM101) in the presence and absence ofthe metabolic activation system.

From the above results, under the test conditions, the test substanceDGF-EX was judged not to be mutagenic.

3-2 Chromosome Aberration Assay

In order to confirm genotoxicity of extract of flower of Daphne genkwa achromosome aberration assay was per formal on the basis of theguidelines of Ministry of Food and Drug Safety in Biotoxtech, a GLP(Good Laboratory Practice) organization.

To confirm the structural aberration of the chromosome of DG-EX obtainedin Example 1, the presence of structural aberration of the chromosomewas evaluated using CHL (Chinese Hamster Lung)/IU cells, a mammaliancell line.

(1) Cell Proliferation Inhibition Test

For the highest capacity setting of this test, the chromosome aberrationassay cell proliferation inhibition test was carried out with thehighest close of DGF-EX 5,000 μg/mL at the following doses of 2,500,1,250, 625, 313, 156, 78.1, 39.1, and 19.5 μg/ml.

As a result, cytotoxicity was observed in the presence or absence of themetabolic activation system and in the absence of the metabolicactivation system of the continuous treatment method. The dose thatspecifically inhibited cell proliferation by more than 50% was more than625 μg/mL in the presence and absence of the metabolic activation systemof the short-term treatment method and more than 156 μg/ml in theabsence of the metabolic activation system of the continuous treatmentmethod. As a result of calculating the capacity to inhibit about 55%cell proliferation, 428.3 μg/mL in the absence of the metabolicactivation system and 725 μg/mL in the presence of the metabolicactivation system of the short-term treatment method, and 133.1 μg/ml inthe absence of the metabolic activation system of the continuoustreatment method.

Therefore, the capacity of this test was set as shown in Table 8 below.Also, a negative control and a positive control were set.

TABLE 8 treatment S9 mix dose of the present test (μg/mL) short-termtreatment − 430, 215, 108, 53.8 + 730, 365, 183, 91.3 continuoustreatment − 140, 70.0, 35.0, 17.5(2) Chromosome Aberration Assay

As a result of the chromosome aberration assay, the frequency of cellswith numerical aberration were less than 5% in the presence and absenceof the metabolic activation system of the short-term treatment methodand in the absence of the metabolism activity system of the continuoustreatment method, and no chromosome aberration was observed, and nostatistical significance was observed when compared with the negativecontrol group. In the positive control group for each treatment group,the frequency of cells with aberrations was more than 10%, which wasstatistically significantly increased when compared to that in thenegative control group. The results are shown in Table 9 below.

TABLE 9 No. of Number of cells with structural aberrations Number ofcells with Test Dose RPD S9 Trt-Rec cell gap total(%) numericalaberrations substance (μg/mL) (%) mix Time(hr) analyzed ctb csb cte csefrg ctg csg gap− gap+ end pol total (%) Others^(a)) Dimethyl 0 100 −6-18 100 1 0 0 0 0 0 0 2 2 0 0 0 0 sulfoxide 100 1 0 0 0 0 0 0 (1.0)(1.0) 0 0 (0.0) DGF-EX 53.6 102 − 6-18 100 not observed 100 108 102 −6-18 100 0 0 0 0 0 0 0 0 0 0 0 0 0 100 0 0 0 0 0 0 0 (0.0) (0.0) 0 0(0.0) 215 97.6 − 6-18 100 0 0 1 0 0 0 0 1 1 0 1 1 0 100 0 0 0 0 0 0 0(0.5) (0.5) 0 0 (0.5) 430 75.0 − 6-18 100 0 0 1 0 0 0 0 1 1 0 3 5 0 1000 0 0 0 0 0 0 (0.5) (0.5) 0 2 (2.5) MMC 0.1 80.4 − 6-18 100 5 0 18 0 0 00 38* 38 0 2 2 0 100 4 0 14 0 0 0 0 (19.0) (19.0) 0 0 (1.0) Dimethyl 0100 + 6-18 100 0 0 0 0 0 0 0 1 1 0 1 1 0 sulfoxide 100 1 0 0 0 0 0 0(0.5) (0.5) 0 0 (0.5) DGF-EX 91.3 104 + 6-18 100 not observed 100 18398.4 + 6-18 100 0 0 0 0 0 0 0 0 0 0 0 0 0 100 0 0 0 0 0 0 0 (0.0) (0.0)0 0 (0.0) 365 77.4 + 6-18 100 1 0 0 0 0 0 0 2 2 1 1 2 0 100 1 0 0 0 0 00 (1.0) (1.0) 0 0 (1.0) 730 53.4 + 6-18 100 0 0 2 0 0 0 0 2 2 0 3 2 0100 0 0 9 0 0 0 0 (1.0) (1.0) 0 2 (1.0) B[a]P 20 57.4 + 6-18 100 5 0 150 0 0 0 31* 32 0 0 0 0 100 2 0 13 0 0 1 0 (15.5) (16.0) 0 0 (0.0)Dimethyl 0 100 − 24-0  100 0 0 0 0 0 0 0 0 0 0 1 1 0 sulfoxide 100 0 0 00 0 0 0 (0.0) (0.0) 0 0 (0.5) DGF-EX 17.5 97.0 − 24-0  100 not observed100 35.0 94.4 − 24-0  100 2 0 0 0 0 0 0 2 2 0 1 1 0 100 0 0 0 0 0 0 0(1.0) (1.0) 0 0 (0.5) 70.0 93.5 − 24-0  100 0 0 0 0 0 0 0 1 1 0 1 1 0100 0 1 0 0 0 0 0 (0.5) (0.5) 0 0 (0.5) 140 57.1 − 24-0  100 0 0 0 0 0 00 1 2 0 1 1 0 100 0 1 0 0 0 1 0 (0.5) (1.0) 0 0 (0.5) MMC 0.1 66.0 −24-0  100 6 0 25 0 0 0 0 52* 52 0 0 0 0 100 6 1 20 1 0 0 0 (26.0) (26.0)0 0 (0.0) Abbreviation: ctg: chromatid gap, csg: chromosome gap, ctb:chromatid break, cte: chromatid exchange, csb: chromosome break, cse:chromosome exchange, frg: fragmentation, end: endoreduplication, pol:polyploidy, MMC: Mitomycin C, B[a]P: Benzo[a]pyrene, RPD: RelativePopulation Doubling, Trt-Rec time: Treatment-Recovery times, gap−: totalnumber of cells with structural aberration except gap, gap+: totalnumber of ceils with structural aberration including gap ^(a))Excludedfrom the number of cells with chromosomal aberrations *p < 0.01

From the above results, the chromosomal abnormality of the testsubstance DGF-EX was judged to be negative under this test condition.

Example 4: Confirming the Effect of the Extract of Flower of Daphnegenkwa on the Nurr1 Activity

To confirm the Nurr1 activation effect of DGF-EX obtained in Example 1,Nurr1 activity experiments were performed using the GAL4 assay system.

After a GAL4-LBD plasmid a luciferase plasmid to which GAL4 can bind,and β-galactosidase were transfected into BE(2)C cells, which areneuroblasts of human origin, DGF-EX was treated for 16 hours atconcentrations of 1, 25 and 40 ppm. The cells thus treated were culturedin a 5% carbon dioxide incubator at 37° C. for 20 hours, and the extractwas dissolved in DMSO and treated. The control group was treated with 1%DMSO and then subjected to luciferase fluorescence analysis. The resultsare shown in FIG. 3.

As shown in FIG. 3 it was confirmed that the activity of Nurr1 wasincreased by DGF-EX in BE(2)C cells. DGF-EX significantly activatedNurr1 at concentrations of 1 ppm and 25 ppm. In particular, DGF-EXshowed maximum activity when treated at a concentration of 25 ppm, andexhibited Nurr1 activating activity about twice as much as the control.

Also, the Nurr1 activity of DGF-EX and DG-EX obtained in ComparativeExample 1 was compared in the same manner as described above, and theresults are shown in FIG. 4.

As shown in FIG. 4, DGF-EX showed 21, 23 and 120% higher activity at 1,10 and 50 ppm than DG-EX, respectively.

Example 5: Identification of the Effect of the Extract of Flower ofDaphne genkwa Animal Model of Parkinson's Disease

This study was carried out to investigate the effect of the extract offlower of Daphne genkwa in animal models of Parkinson's disease.

In order to specifically kill dopaminergic neurons in substantia nigraof midbrain, 6 OHDA (0.2 μg/μl, final volume 5 μl) was directly injectedinto the AP(−4.3), ML(−1.8), DV(−8.2), and AP(−5.0), ML(−1.8), DV(−8.2)regions of the brain using a stereotaxic tool in 18 6-week-old SD rats(Coatec) to produce an animal model of Parkinson's disease asexperimental group. Desipramine was administered at a dose of 25 mg/kg30 minutes before the administration of 6-OHDA to inhibit cell deathother than dopaminergic neurons. As a control group, 6 6-week-old SDrats (Coatec) were injected with PBS instead of 6-OHDA.

Six of the 6-OHDA-lesioned 18 rats were vehicle treated (control group),and another 6 rats were fed a diet supplemented with 50 mg/kg of thedaily dose of the extract of flower of Daphne genkwa, and the remaining6 rats were fed a diet supplemented with 100 mg/kg of the daily dose ofthe extract of flower of Daphne genkwa.

A rotation test was performed at two and 4 weeks after surgery. When thedopamine receptor agonist, apomorphine is injected into an animal modelof Parkinson's disease, a denervation supersensitivity of dopamineinduces rotation to the opposite side of the lesion, which can bemeasured quantitatively using a rotometer. The results are shown in FIG.5.

As shown in FIG. 5, it was confirmed that the extract of flower ofDaphne genkwa was significantly reduced in the rats fed with the feedcontaining the rotomain of the apomorphine after two and 4 weeks evenwhen administered at a low concentration in comparison with the usualadministration concentrations of the extract of root of Daphne genkwa.

Example 6: Immunohistochemical Analysis of the Effect of the Extract ofFlower of Daphne genkwa in Animal Model of Parkinson's Disease

In Example 5, the therapeutic effect in the animal model of Parkinson'sdisease of the extract of flower of Daphne genkwa was confirmed, and wefurther investigated whether the death of dopaminergic neurons in thesubstantia nigra of midbrain was actually inhibited by theadministration of the extract of flower of Daphne genkwa.

An animal model of Parkinson's disease was prepared in the same manneras in Example 5, and rats were sacrificed at 4 weeks after the surgery,and followed by perfusion with 4% paraformaldehyde. Brains were removed,and cut into a 40 μm coronal section using a vibratome and thensubjected to immunostaining with a tyrosine hydroxylase antigen. Thesections were treated with 3% hydrogen peroxide solution and washed 3times with PBS. Then, after the sections were blocked with 5% horseserum for 1 hour at room temperature, tyrosine hydroxylase antigen wastreated overnight at 4° C. The sections were washed with PBS and thentreated with secondary antirabbit IgG and treated withavidin-biotinylated peroxidase complex and 3,3′-diaminobenzidine.

The color-developed and dyed dopaminergic neurons were observed under amicroscope. The results are shown in FIG. 6, and the number of neuronswas counted, and the results are shown in FIG. 7.

As shown in FIG. 6, when the left substantia nigra (6-OHDA) injectedwith 6-OHDA was compared with the right substantia nigra (unlesioned)not injected, for vehicle treated rats the dopaminergic neurons in6-OHDA-injected substantia nigra were significantly reduced whencompared with normal substantia nigra. However, when 10 mg/kg and 50mg/kg of the extract of flower of Daphne genkwa (DGF) were administered,the level of neurons similar to that of the normal substantia nigra wasmaintained even in the case of 6-OHDA-injected substantia nigra.

Furthermore, as shown in FIG. 7, when 6-OHDA was injected, 97.5% ofdopaminergic neurons were killed, but it was confirmed that theadministration of 10 mg/kg and 50 mg/kg of the extract of flower ofDaphne genkwa (DGF) significantly inhibited the death of dopaminergicneurons (39.6% and 70.1%, respectively)

This indicates that the extract of flower of Daphne genkwa (DGF)strongly inhibited dopaminergic neurons death by 6-OHDA.

What is claimed is:
 1. A tablet or capsule consisting essentially of anextract of a flower of Daphne genkwa, polyvinylpyrrolidone, acaciarubber, and polyethylene glycol.
 2. The tablet or capsule of claim 1,wherein the extract consists essentially of Genkwanin N or Yuanhuacine.3. A method for inhibiting the activity of Nurr1 in a human sufferingfrom a neurodegenerative disease consisting essentially of administeringtherapeutically effective amounts of an extract of a flower of Daphnegenkwa, polyvinylpyrrolidone, acacia rubber, and polyethylene glycol tothe human suffering from the neurodegenerative disease.
 4. The method ofclaim 3, wherein the neurodegenerative disease is Parkinson's disease.5. The method of claim 3, wherein the extract consists essentially ofGenkwanin N or Yuanhuacine.